I canīt remember a TATL flight in C/J where there wasnīt a vegetarian option, usually some kind of pasta and sauce.
Dinner consists of appetizer (currently salmon if Iīm not mistaken) + salad + choice of 4 main courses (usually 1 fish, 2 meat, 1 vegetarian) + cheese + dessert (pecan pie with ice cream IIRC)
Breakfast will definitely be vegetarian as AC only serves a light continental breakfast: fresh croissants and pastries, preserves, fresh fruit and coffee/tea.
YOW-FRA is a very short flight anyway, on TATL flight East Coast - Europe I tend to order the express meal option and skip breakfast in order to maximize the amount of sleep.